Large containers of typically one-quart to fifteen gallons are in widespread usage for holding a wide variety of products such as paint, solvents, liquids, and dry products such as chemicals, plastic precursors, and the like. Many or most of these containers are of the wide-mouthed type, where the mouth of the container is almost as wide as the maximum diameter of the container, with the lid fitting in some form of snap-fit manner on the lip of the container.
A wide variety of designs has been proposed for containers of this type. As one method of testing such designs for efficacy and practicality, they are subject to drop tests. The container is filled with liquid, closed with a lid across its wide mouth, and dropped in inverted position from a height ranging from 24 inches to 4 feet, to see if the lid will pop off under such stress. Such testing obviously eliminates a large number of the many proposed designs for wide-mouthed, large containers.
Particularly, large, square containers have had difficulty in passing drop testing. Also, square containers have difficulties of sealing, since O-rings at the mouths of such containers which form a seal between the container and lid are more likely to form leaks at the corners than is the case with cylindrical containers.
Accordingly, there is a need for large, molded plastic, wide-mouthed containers which both pass stringent drop testing and which are of reduced costs when compared with the current commercial, rectangular containers. Also, there is a need for large, rectangular containers which have good sealing with or without an O-ring, which sometimes performs in a deficient manner in rectangular containers by permitting leakage at the corners.
By this invention, such a container and lid is provided, having greatly improved resistance to lid pop-off. The container and lid can be preferably of rectangular cross-section, although the invention may be used with cylindrical containers, or containers of other shapes, if and as desired, with or without O-rings for sealing. Also, the invention can be used between any desired, connectable articles and not just wide-mouthed containers with sealable lids: for example, one, two or multiple piece housings or casings for various items such as television sets or other appliances, machinery, instrumentation, or the like. The two-piece, connectable article of this invention may actually comprise multiple pieces if desired, with various pieces using the invention described herein, but for simplicity, they are all described as a "two-piece connectable article" since they have two pieces that connect in accordance with this invention.
Such articles can be snapped together with ease; can exhibit a sealing function together if desired; and are not effectively separable without the destruction of certain parts of the system, to provide a tamper-proof indication that the closed system has been opened. Also, the respective pieces of the connectable article of this invention can be easily molded if desired, although the pieces could have resilient metal components if desired, formed by a non-molding process. All things being equal, the molding of the respective pieces can be inexpensive relative to competing systems.
Also, the containers and other connectable articles of this invention can have a clear, tamper-evident feature, showing when they have been initially opened.